Comparison of birds and pterosaurs, the two archosaurian flyers, sheds light on adaptation to an aerial lifestyle. The neurological basis of control holds particular interest in that flight demands on sensory integration, equilibrium, and muscular coordination are acute. Here we compare the brain and vestibular apparatus in two pterosaurs based on high-resolution computed tomographic (CT) scans from which we constructed digital endocasts. Although general neural organization resembles birds, pterosaurs had smaller brains relative to body mass than do birds. This difference probably has more to do with phylogeny than flight, in that birds evolved from nonavian theropods that had already established trends for greater encephalization. Orientation of the osseous labyrinth relative to the long axis of the skull was different in these two pterosaur species, suggesting very different head postures and reflecting differing behaviours. Their enlarged semicircular canals reflect a highly refined organ of equilibrium, which is concordant with pterosaurs being visually based, aerial predators. Their enormous cerebellar floccular lobes may suggest neural integration of extensive sensory information from the wing, further enhancing eye- and neck-based reflex mechanisms for stabilizing gaze.

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Six associated rhynchosaur skeletons, recently discovered by the Geological Studies Unit of the Indian Statistical Institute in the Upper Triassic Maleri Formation, allow an almost complete osteological description and restoration of the species Paradapedon huxleyi . The dentition is highly specialized, ankylothecodont, each tooth firmly fixed with a long root, new teeth added posteriorly in diagonal rows, without tooth replacement. The creatures probably lived in flood-plains or marshy environments, as shell eaters feeding mainly on mussels. Possible evolutionary trends within the family Rhynchosauridae are outlined. The seven genera of rhynchosaurs are grouped on their morphological characters into three well-defined subfamilies which represent three stages in rhynchosaur evolution, occurring in Lower, Middle and Upper Triassic respectively.

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